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Re: An online circle intersection fractal...

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> "Michael Haufe (TNO)"  wrote in message news:34ae1ec8-f301-4a46-bdc1-> 
> f2c2be3d7d4a@googlegroups.com...

> On Monday, November 4, 2013 4:01:19 PM UTC-6, Chris M. Thomasson wrote:
> >
> > Do you happen have something in mind that can find the true 
> > intersection(s)
> > of two circles that gets around any sqrt wrt polar coordinates? I am all
> > ears if you have something to share!   ;^)

> I thought about it a little more, and my thought is
> that because you are creating a fractal consisting
> of a significant number of circles any form of
> calculation like the one you are using or the one
> I was initially thinking is going to be terrible in
> performance.

AFAICT, it's almost impossible to disagree with that
statement Michael!

;^o



> If you instead follow my idea of directly plotting
> the circles on the pixel array itself, you could
> find the intersection points with no calculation at
> all:

> setOfIntersectPoints.concat(plotCircle(x,y,r));

> when you draw the circle on the pixel array, you
> can look at the color of the current pixel before
> you plot the point. So if the default color of the
> canvas is white, and circles are black when plotted,
> the intersection of the current circle and ALL of
> the relevant circles in the region would be where
> the pixel is already black.

There has to be a way to do this using the Bresenham
algorithm. I am worried about circles that go through
each other when the pixels go diagonal. Which means
the current circle would not pick up its intersection(s).

Perhaps the currently encoded circle could be a
different color. Therefore it could do a little search
for other circles, and disregard colors that match
itself.

Need to think.


Thanks Michael.

:^) 

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Thread

An online circle intersection fractal... "Chris M. Thomasson" <no@spam.invalid> - 2013-11-02 13:43 -0700
  Re: An online circle intersection fractal... "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2013-11-03 17:55 -0800
  Re: An online circle intersection fractal... "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2013-11-03 18:55 -0800
    Re: An online circle intersection fractal... "Chris M. Thomasson" <no@spam.invalid> - 2013-11-04 14:01 -0800
      Re: An online circle intersection fractal... "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2013-11-04 18:40 -0800
        Re: An online circle intersection fractal... "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2013-11-04 18:42 -0800
        Re: An online circle intersection fractal... "Chris M. Thomasson" <no@spam.invalid> - 2013-11-05 13:05 -0800
          Re: An online circle intersection fractal... "Chris M. Thomasson" <no@spam.invalid> - 2013-11-05 14:35 -0800
            Re: An online circle intersection fractal... "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2013-11-10 23:48 -0800
        Re: An online circle intersection fractal... Dr J R Stockton <reply1300@merlyn.demon.co.uk.invalid> - 2013-11-06 19:41 +0000
          Re: An online circle intersection fractal... "Chris M. Thomasson" <no@spam.invalid> - 2013-11-07 12:46 -0800
    Re: An online circle intersection fractal... "Chris M. Thomasson" <no@spam.invalid> - 2013-11-04 14:03 -0800
  Re: An online circle intersection fractal... "Chris M. Thomasson" <no@spam.invalid> - 2013-11-05 22:19 -0800

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